Actuation mechanism with grooved actuation levers

ABSTRACT

Particular embodiments disclosed herein provide a surgical instrument comprising a device having a proximal end and a functional end configured to be inserted into a body part, an assembly having a proximal end and a distal end, a shaft coupled to the proximal end of the assembly, the shaft having a shaft housing, a bearing positioned around the assembly, wherein the bearing is configured to slide over the assembly, a hub having a sleeve tube. The basket comprises a plurality of grooved levers, each grooved lever having a proximal end received by the shaft housing and a distal end coupled to a tip of the basket, wherein compressing one or more of the plurality of grooved levers moves the bearing and the hub relative to the shaft and toward the functional end of the device, causing the sleeve tube to transition the device from the deactivated state to an activated state.

PRIORITY CLAIM

This application claims the benefit of priority of U.S. ProvisionalPatent Application Ser. No. 62/893,285 titled “ACTUATION MECHANISM WITHGROOVED ACTUATION LEVERS,” filed on Aug. 29, 2019, whose inventors areNiels Alexander Abt, Reto Grueebler, Timo Jung, Thomas Linsi and NiccoloMaschio, which is hereby incorporated by reference in its entirety asthough fully and completely set forth herein.

TECHNICAL FIELD

The present disclosure relates generally to a surgical instrument withan actuation mechanism including grooved actuation levers.

BACKGROUND

During certain surgical procedures (e.g., ophthalmic procedures) asurgeon is required to manipulate (e.g., remove, cut, peel, etc.)certain tissues within a body part by using forceps, scissors, etc.Examples of such surgical procedures are internal limiting membrane(ILM) removal and epiretinal membrane (ERM) removal for treatingdifferent macular surface diseases. During such procedures, a surgeoninserts the tip of a surgical instrument, which, for example, functionsas forceps, into a patient's eye globe and uses the forceps to grasp andpeel the ILM/ERM. Certain designs are currently used for providing asurgical instrument with an actuation mechanism that allows a surgeon toclose and open the jaws of the forceps or scissors, which are located atthe tip of a surgical instrument. However, in certain cases, theexisting actuation mechanisms may, among other things, require too muchactuation force and be difficult to assemble.

BRIEF SUMMARY

The present disclosure relates generally to a surgical instrument withan actuation mechanism including grooved actuation levers.

Particular embodiments disclosed herein provide a surgical instrumentcomprising a device having a proximal end and a functional endconfigured to be inserted into a body part, an assembly having aproximal end and a distal end, wherein the distal end of the assembly iscoupled to the proximal end of the device, a shaft coupled to theproximal end of the assembly, the shaft having a shaft housing, abearing positioned around the assembly, wherein the bearing isconfigured to slide over the assembly, a hub having a sleeve tube,wherein the sleeve tube is configured to partially house the device suchthat the functional end of the device at least partially extends beyonda distal end of the sleeve tube when the device is in a deactivatedstate, and a basket coupled to the hub. The basket comprises a pluralityof levers, each grooved lever having a proximal end received by theshaft housing and a distal end coupled to a tip of the basket, whereincompressing one or more of the plurality of grooved levers moves thebearing and the hub relative to the shaft and toward the functional endof the device, causing the sleeve tube to transition the device from thedeactivated state to an activated state.

The following description and the related drawings set forth in detailcertain illustrative features of one or more embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The appended figures depict certain aspects of the one or moreembodiments and are therefore not to be considered limiting of the scopeof this disclosure.

FIG. 1 illustrates an example of a surgical instrument with a prior artactuation mechanism.

FIG. 2 illustrates a perspective view of an example surgical instrument,in accordance with certain embodiments of the present disclosure.

FIG. 3 illustrates a perspective view of a hub and a basket of thesurgical instrument of FIG. 2, in accordance with certain embodiments ofthe present disclosure.

FIG. 4 illustrates an exploded view of some of the components of thesurgical instrument of FIG. 2, in accordance with certain embodiments ofthe present disclosure.

FIGS. 5A-5C illustrate different views of a snapper assembly of thesurgical instrument of FIG. 2, in accordance with certain embodiments ofthe present disclosure.

FIG. 6A illustrates a cross sectional view of the surgical instrument ofFIG. 2, when levers of the surgical instrument are in their at-reststate, in accordance with certain embodiments of the present disclosure.

FIG. 6B illustrates a cross sectional view of the surgical instrument ofFIG. 2, when levers of the surgical instrument are in their compressedstate, in accordance with certain embodiments of the present disclosure.

FIGS. 7A-7B illustrate different views of the hub of the surgicalinstrument of FIG. 2, in accordance with certain embodiments of thepresent disclosure.

To facilitate understanding, identical reference numerals have beenused, where possible, to designate identical elements that are common tothe drawings. It is contemplated that elements and features of oneembodiment may be beneficially incorporated in other embodiments withoutfurther recitation.

DETAILED DESCRIPTION

Particular embodiments of the present disclosure provide a surgicalinstrument with an actuation mechanism including grooved actuationlevers.

FIG. 1 illustrates an example of a surgical instrument with a prior artactuation mechanism. As shown, surgical instrument 100 comprises ahandle 102, a basket 103 comprising a plurality of actuation levers 104,a housing 105, an actuation tube 106, and a device, shown as forceps108, at the tip of the probe. Each actuation lever 104 comprising afirst leg 112 and a second leg 110 joined at flexible juncture 114. Inother embodiments, the first leg 112 and second leg 110 may be separatepieces coupled together with a hinge. Each actuation lever 104 may bemade from material such as shape memory material, titanium, stainlesssteel, suitable thermoplastic, etc. Actuation tube 106 may be anysuitable medical grade tubing, such as titanium, stainless steel, orsuitable polymer and is sized so that forceps 108 reciprocate easilywithin. Forceps 108 are generally made from stainless steel or titanium,but other materials may also be used.

Surgical instrument 100 is designed so that in use, when the pluralityof actuation levers 104 are in their relaxed state, forceps 108 protrudeor extend beyond the distal end of actuation tube 106, which is coupledto a housing 105. Squeezing one or more of the actuation levers 104causes the respective actuation lever 104 to flex at juncture 114,pushing housing 105 forward relative to handle 102. The forward movementof housing 105 is transferred to actuation tube 106, causing actuationtube 106 to slide forward over a distal portion of the jaws of forceps108, thereby activating forceps 108 by compressing together the jaws. Byclosing jaws of forceps 108, the surgeon is able to, for example, graspand peel a tissue (e.g., ILM) within a body part.

In the example of FIG. 1, the actuation mechanism may, among otherthings, require too much actuation force and be too difficult toassemble. In addition, basket 203 is long and has a large diameter,which may make basket 203 too bulky. Accordingly, certain embodimentsdescribed herein relate to a surgical instrument with an actuationmechanism including grooved actuation levers. In particular embodiments,this may reduce the structural complexity of the actuation mechanism andallow for easier assembly.

FIG. 2 illustrates a perspective view of an example surgical instrument200 in accordance with the teachings of the present disclosure. As shownin FIG. 2, surgical instrument 200 comprises a rear cap 202, a shafthousing 204, a basket 203 comprising actuation levers (“levers”) 205, anadjustable hub (“hub”) 212 coupled to a sleeve tube 214, and device 216.

Although in the example of FIG. 2, device 216 is shown as forceps,generally device 216 may be any surgical device that is shaped to fit insleeve tube 214 with a distal end that is referred to as a functionalend (e.g., a movable or active end). For example, device 216 may beshaped as a needle with a functional end, which may comprise forceps,scissors, etc., with jaws or arms. The proximal end of device 216 iscoupled to a coupling tube of a snapper assembly, as shown in FIGS. 3,4, 5A-5B, etc.

As used herein, the term “proximal” refers to a location with respect toa device or portion of the device that, during normal use, is closest tothe clinician using the device and farthest from the patient inconnection with whom the device is used. Conversely, the term “distal”refers to a location with respect to the device or portion of the devicethat, during normal use, is farthest from the clinician using the deviceand closest to the patient in connection with whom the device is used.

Basket 203 couples to shaft housing 204 at its proximal end and to hub212 at its distal end. Shaft housing 204 is part of a shaft that extendslongitudinally within basket 203. At its proximal end, the shaft couplesto rear cap 202. Basket 203 comprises levers 205, each lever 205including a first leg 206 and a second leg 210, the second leg 210comprising a grooved segment 208. In certain aspects, the length offirst leg 206 may be in the range of 18-30 millimeters (mms), the lengthof grooved segment 208 may be in the range of 4-8 mms, and the length ofthe second leg 210 may be in the range of 9-18 mms. Grooved segments 208of levers 205 allow a user, such as a surgeon, to more easily grasp andactuate surgical instrument 200 as compared to the prior art basketdesign shown in FIG. 1. The outer diameter of basket 203, where thegrooved segments 208 are, is smaller than the outer diameter of basket203 where the distal ends of first legs 206 or the proximal ends of theun-grooved segments of the second legs 210 are. For example, the outerdiameter of basket 203, where the grooved segments 208 are, is 0.1 to0.8 millimeters (mms) smaller than the outer diameter of basket 203where the distal ends of first legs 206 or the proximal ends of theun-grooved segments of the second legs 210 are.

Each lever 205 also comprises three moving joints or junctures 207, 209,and 211, which allow the lever to extend when it is compressed. Morespecifically, each lever 205 comprises a tail joint 207, a main joint209, and a head joint 211, which allow the lever to bend and extend.These joints allow basket 203 to be compressed thereby pushing hub 212along with sleeve tube 214 forward relative to shaft housing 204. Incertain embodiments, each of tail joint 207, main joint 209, and headjoint 211 may comprise a hinge.

Although not shown, the inner surface of hub 212 and the outer surfaceof the distal end of basket 203 may be threaded, thereby allowing hub212 to be screwed on to the distal end of basket 203. Hub 212 isadjustable meaning that, during the manufacturing process, screwing hub212 clockwise or counterclockwise allows for adjusting how far thefunctional end of device 216 extends beyond the distal end of sleevetube 214. For example, a larger portion of the functional end of device216 protrudes beyond sleeve tube 214 when hub 212 is fully rotated orscrewed on to the distal end of basket 203. By screwing hub 212counterclockwise, however, hub 212 and sleeve tube 214 move in a distaldirection relative to basket 203, which causes the distal end of sleevetube 214 to cover a larger portion of the functional end of device 216,as compared to when hub 212 is fully screwed on to the distal end ofbasket 203.

Surgical instrument 200 is designed so that in use, when levers 205 arein their relaxed or at-rest state (i.e., not compressed), the functionalend of device 216 protrudes or extends beyond the distal end of sleevetube 214. In other words, sleeve tube 214 only partially covers thefunctional end of device 216. When levers 205 are compressed, the distalend of basket 203 is pushed forward relative to shaft housing 204 anddevice 216. The forward movement of the distal end of basket 203 istransferred to hub 212 and then sleeve tube 214, causing sleeve tube 214to slide forward and activate device 216. Device 216 is activated as aresult of the forward movement of sleeve tube 214, which presses thejaws or arms of device 216 together. An activated device refers to adevice whose jaws or arms are closed. Note that FIG. 2 illustrateslevers 205 in their at-rest state while FIG. 6B illustrates a crosssectional view of surgical instrument 200 when levers 205 arecompressed.

Levers 205 are made from flexible but resilient material to allow levers205 to be compressed and then pushed back into their at-rest positions.In one example, levers 205 may be made from polyoxymethylene (POM). Notethat in the example of FIG. 2, surgical instrument 200 comprises 12levers 205. However, a fewer or larger number of levers 205 may be usedin other embodiments. For example, surgical instrument 200 may havebetween 10-16 levers.

FIG. 3 illustrates a perspective view of hub 212 and basket 203 ofsurgical instrument 200 separately. As shown, hub 212 can be screwed onto a threaded tip or segment 313 of basket 203. FIG. 3 also shows acoupling tube 315 of a snapper assembly that is positioned inside ofbasket 203. Coupling tube 315 protrudes outside or beyond threadedsegment 313. The distal end of coupling tube 315 is configured to becoupled to a proximal end of a needle of device 216. In someembodiments, the distal end of coupling tube 315 and the proximal end ofthe needle of device 216 are crimped together. FIG. 3 also shows a cap316 that is configured to house hub 212. Cap 316 is placed on hub 212upon the completion of the manufacturing process, which includes theadjustment of hub 212. FIG. 3 also shows the proximal end 301 of theshaft, described in further detail below. Proximal end 301 of the shaftis configured to be coupled to rear cap 202.

FIG. 4 illustrates an exploded view of some of the components ofsurgical instrument 200. As shown, basket 203 comprises an insert 422 atits proximal end, which is configured to be inserted into a cylindricalopening between the body of shaft 418 and shaft housing 204. Morespecifically, insert 422, in some embodiments, may be friction-lockedinto the opening. Shaft 418 comprises an extended cylindrical portion419 that is configured to longitudinally extend within basket 203. Shaft418 comprises a hollow compartment to allow the proximal end of snapperassembly 426 to be inserted (or received) and snapped therein, asfurther described in relation to FIGS. 6A-6B.

Also shown is a bearing 420, which is configured to be positioned at thedistal end of cylindrical portion 419 of shaft 418. As shown in FIGS. 6Aand 6B, bearing 420 is also configured to slide on snapper assembly 426after snapper assembly 426 is snapped into the hollow compartment ofshaft 418. Bearing 420 is also configured to be housed by a bearinghousing of basket 203, as shown in FIGS. 6A and 6B in more detail. Whenlevers 205 are in their at-rest state, the proximal end 421 of bearing420 and the distal end 423 of shaft 418 are in contact. However, whenlevers 205 are in their compressed state, bearing 420 slides forwardrelative to shaft 418 and snapper assembly 426 such that the proximalend 421 of bearing 420 and the distal end 423 of shaft 418 are no longerin contact. Bearing 420′s inner surface is made of or comprises materialthat has a low friction coefficient with respect to the outer surface ofthe snapper assembly 426. As a result, utilizing bearing 420 in theactuation mechanism described herein is advantageous because it allowsfor a smoother actuation, as bearing 420 is able to smoothly slide backand forth on snapper assembly 426.

Snapper assembly 426 comprises a needle-shaped proximal end 430, which,as described above, is configured to be inserted into the hollowcompartment of shaft 418. Snapper assembly 426 also comprises wings 428,which are biased outwardly and configured to snap into the hollowcompartment of shaft 418. Once wings 428 snap into the hollowcompartment, snapper assembly 426 does not move relative to shaft 418.Different views of snapper assembly 426 are shown in FIGS. 5A-5C, whichillustrate wings 428 more clearly. Snapper assembly 426 also comprises acylindrical element 427 around which spring 424 is configured to bepositioned. The distal end of spring 424 is positioned against barrier429 of snapper assembly 426. When basket 203 is compressed, the distalend of threaded segment 313 moves in a distal direction relative toshaft 418 and compresses spring 424 against barrier 429. As a result,spring 424 becomes loaded or charged, thereby causing basket 203 totransition or snap back into its at-rest position when the user releasesbasket 203.

Utilizing the basket design of basket 203 in the actuation mechanismdescribed herein is advantageous because less actuation force isrequired to compress basket 203 and thereby activate the device (e.g.,device 216) used in conjunction with or as part of surgical instrument200. More specifically, the diameter of basket 203 (e.g., in the rangeof 11-23 mms) is smaller at or over the grooved segment 208 of basket203 as compared to the diameter of basket 103, of the prior artactuation mechanism, at junctures 114. As a result, with the actuationmechanism described herein a lower amount of force is applied to spring424 and, therefore, a lower amount of opposite spring force isexperienced by the user when compressing basket 203. Also, as describedabove, grooved segments 208 of levers 205 allow for a user to moreeasily grasp and compress basket 203. In certain aspects, spring 424'sspring constant is in the range of 0.2-1 Newton/millimeter (N/mm).

FIGS. 5A-5C illustrate different views of snapper assembly 426. FIG. 5Aillustrates a perspective view of snapper assembly 426, which compriseswings 428 a and 428 b, barrier 429 and cylindrical element 427. FIG. 5Billustrates a side view of snapper assembly 426. FIG. 5C illustrates across sectional view of snapper assembly 426.

FIG. 6A illustrates a cross sectional view of surgical instrument 200when levers 205 are in their at-rest state. As shown, insert 422 ispositioned within the cylindrical opening between the body of shaft 418and shaft housing 204. Also shown is snapper assembly 426, which issnapped into a hollow compartment 632 of shaft 418. As described above,wings 428 a-428 b are biased outwardly such that to insert snapperassembly 426 into hollow compartment 632, wings 428 a-428 b would haveto be pushed inwardly towards a longitudinal axis of snapper assembly426.

During the assembly process of surgical instrument 200, needle-shapedproximal end 430 may be used as a guide to insert snapper assembly 426into hollow compartment 632. At a certain point, by pushing snapperassembly 426 far enough, wings 428 a-428 b snap into hollow compartment632. More specifically, once snapper assembly 426 is fully inserted intohollow compartment 632, the tips of wings 428 a-428 b snap into thedistal end of hollow compartment 632, at which point the inner diameterof shaft 418 is larger. What allows the tips of wings 428 a-428 b tosnap into the distal end of hollow compartment 632 is the difference inthe inner diameter of shaft 418 at its different portions. For example,as shown, shaft 418 has a smaller inner diameter at portion 636 incomparison with the inner diameter of shaft 418 at the distal end ofhollow compartment 632. Once wings 428 a-428 b snap into hollowcompartment 632, snapper assembly 426 is locked in place and can nolonger be separated from shaft 418 because the proximal end of portion636 acts as a barrier against the tips of wings 428-428 b.

As shown, the distal end 423 of shaft 418 is in contact with theproximal end 421 of bearing 420 when levers 205 are in their at-reststate. Bearing 420 is positioned in an opening between bearing housing638 and snapper assembly 426. More specifically, the opening is providedbetween the inner surface of bearing housing 638, which is cylindricallyshaped, and the outer surface of snapper assembly 426. As shown, thedistal end of bearing 420 is in contact with the end of the opening,which refers to the proximal end of a slider segment 640 of bearinghousing 638. Slider segment 640 does not make contact with the body ofsnapper assembly 426 and moves relative to shaft 418 when levers 205 arecompressed. Slider segment 640 is positioned at the distal end ofbearing housing 638. As described above, FIG. 6A illustrates levers 205in their at-rest state, meaning that the device (e.g., device 216) is inan inactivated state (e.g., the jaws of the forceps are open).

FIG. 6B illustrates a cross sectional view of surgical instrument 200when levers 205 are in their compressed state. As shown, when levers 205are compressed, the distal end of levers 205 move in a distal direction,meaning slider segment 640 moves in a distal direction, thereby pressingspring 424 against barrier 429, which results in spring 424 exertingopposite spring force against slider segment 640. As shown, bearing 420has moved in a distal direction relative to shaft 418, such that thereis now some space between the proximal end 421 of bearing 420 and thedistal end 423 of shaft 418. As described above, because the innersurface of bearing 420 has a low friction coefficient with the outersurface of snapper assembly 426, bearing 420 is able to smoothly slideover snapper assembly 426, thereby resulting in a smooth actuation. Whenlevers 205 are compressed, the hub and the sleeve tube (e.g., hub 212and sleeve tube 214) move toward the functional end of the device,causing the sleeve tube to transition the device from a deactivatedstate to an activated state (e.g., forceps jaws are closed). Note that,in the example of FIGS. 6A-6B, basket 203 is manufactured as a singlecomponent (e.g., through injection molding), although in some otherembodiments, that need not be the case.

FIGS. 7A-7B illustrate different views of a hub 212. FIG. 7A illustratesa cross-sectional view of hub 212. As shown, hub 212 comprises athreaded opening 752, which allows hub 212 to be screwed on to thethreaded segment 313 of basket 203. Hub 212 also comprises an opening750 through which the position of the device can be adjusted. Forexample, during the assembly process of the surgical device, after hub212 is coupled to basket 203, the proximal end of device 216 may beinserted into the sleeve tube 214 in order to couple the proximal end ofdevice 216 to coupling tube 315 of snapper assembly 426. During thisprocess, the proximal end of device 216 passes through opening 750 andis, therefore, accessible through the opening. As a result, the positionof the device 216 may be adjusted using an instrument that is able tograb on to device 216 through opening 750. For example, device 216 maybe further pushed in to ensure that its proximal end is fully coupled tocoupling tube 315 using such an instrument through opening 750.

FIG. 7B illustrates a side view of hub 212 with a 90-degree rotationabout an axis parallel to sleeve tube 214. As shown, hub 212 comprisestwo openings 750, shown from the side.

The foregoing description is provided to enable any person skilled inthe art to practice the various embodiments described herein. Variousmodifications to these embodiments will be readily apparent to thoseskilled in the art, and the generic principles defined herein may beapplied to other embodiments. Thus, the claims are not intended to belimited to the embodiments shown herein, but are to be accorded the fullscope consistent with the language of the claims.

What is claimed is:
 1. A surgical instrument, comprising: a devicehaving a proximal end and a functional end configured to be insertedinto a body part; an assembly having a proximal end and a distal end,wherein the distal end of the assembly is coupled to the proximal end ofthe device; a shaft coupled to the proximal end of the assembly, theshaft having a shaft housing; a bearing positioned around the assembly,wherein the bearing is configured to slide over the assembly; a hubhaving a sleeve tube, wherein the sleeve tube is configured to partiallyhouse the device such that the functional end of the device at leastpartially extends beyond a distal end of the sleeve tube when the deviceis in a deactivated state; and a basket coupled to the hub, the basketcomprising: a plurality of grooved levers, each grooved lever having aproximal end received by the shaft housing and a distal end coupled to atip of the basket, wherein compressing one or more of the plurality ofgrooved levers moves the bearing and the hub relative to the shaft andtoward the functional end of the device, causing the sleeve tube totransition the device from the deactivated state to an activated state.2. The surgical instrument of claim 1, wherein: each of the plurality ofgrooved levers comprises a first leg and a second leg, the second legcomprising a grooved segment; and a first outer diameter of the basketover grooved segments of the plurality of grooved levers is smaller thana second outer diameter of the basket at distal ends of first legs ofthe plurality of grooved levers and proximal ends of un-grooved segmentsof second legs of the plurality of grooved levers.
 3. The surgicalinstrument of claim 1, wherein: the basket comprises a bearing housing;and the bearing is positioned in an opening provided between the bearinghousing and a body of the assembly.
 4. The surgical instrument of claim3, wherein: a proximal end of the bearing is in contact with a distalend of the shaft when the plurality of levers are in an at-rest state;the device is de-activated when the plurality of levers are in theat-rest state; and the proximal end of the bearing is separated from thedistal end of the shaft when the plurality of levers are compressed. 5.The surgical instrument of claim 1, wherein: the assembly comprises asnapper assembly having one or more wings; and the shaft comprises ahollow compartment configured to receive the proximal end of the snapperassembly and the one or more wings of the snapper assembly.
 6. Thesurgical instrument of claim 5, wherein the one or more wings aresnapped and locked into the hollow compartment.
 7. The surgicalinstrument of claim 1, wherein: the hub comprises a threaded opening;the tip of the basket comprises a threaded segment, wherein the threadedopening is configured to be screwed onto the threaded segment of the tipof the basket; and adjusting a position of the hub with respect to thebasket allows for adjusting how far the functional end of the deviceextends beyond the distal end of the sleeve tube.
 8. The surgicalinstrument of claim 7, wherein the hub comprises two openings throughwhich a position of the device within the surgical instrument can beadjusted and fixed.